Video Auto Dimming And Focusing Based On The Image Information

This system is based on digital image processing technology, using CCD in stead of the eyes to conduct focus dimmer judgment. It reduced the labor intensity of test, reading and tracking the subjective errors, and improved the efficiency of measurement .About CCD dimming focusing of the quality is high. The targets of high-speed flight have a lot of change, so adjusting the real-time optical zoom is also very high.This paper applies method what combine dividing up histogram and using entropy to detect the extent of exposure. The image histogram is divided into different regions .These weighted entropy is balance between the image exposure value and the ideal exposure value. A lot of experiments proved that this algorithm can control the exposure.In the automatic focusing system, this paper analyzed both the domestic and overseas status focal technology, summing up the existing focal method, advanced a new focus algorithm based on image edge gradient. The system overcame the lack of original methods, and improved the efficiency of focal dimming. On the process of dimming at the image focus criterion validation, we designed a set of system that include optics, mechanism, electronics, and computer camera .This system included micro-actuator control, interface card control and digital image processing. A large number of experimental data evidence that this auto-dimming function focal criterion has better accuracy, and can be applied to the actual measurement.